UK puts Google AI on the flight path to fewer contrails

PUBLIC SECTOR

Trial will test whether small route and altitude tweaks can reduce aviation's warming impact

Britain is putting Google AI in the flight-planning loop to see whether airliners can dodge the patches of sky where their vapor trails are most likely to stick around and warm the planet.

The UK government is backing a trial to predict where persistent contrails will form over the North Atlantic and help participating aircraft avoid those areas by adjusting their routes or altitude.

The Department for Transport is putting £2.6 million into the 30-month project, which will combine Met Office weather forecasts with Google's artificial intelligence to suggest alternative flight paths.

Flight tests are scheduled for the winters of 2026-27 and 2027-28. Any route or altitude changes will go through normal air traffic control procedures and require the usual safety checks.

Those white streaks behind aircraft aren't just an opportunity for conspiracy theorists to get excited. Contrails form when water vapor from jet exhaust freezes into ice crystals in cold, humid air. Many disappear quickly, but under the right atmospheric conditions they can hang around, spread out and develop into clouds that trap heat.

Persistent contrails are therefore one of aviation's non-CO₂ contributions to climate change – and potentially one that can be tackled without waiting for airlines to replace their fleets or invent a jet engine that runs on good intentions.

The trial rests on the fact that contrail-friendly conditions occur only in particular regions and layers of the atmosphere. If forecasts can identify them accurately enough, aircraft could fly above, below, or around them.

"We're partnering with Google to back British experts and innovators to find practical ways to make flying cleaner," said aviation minister Keir Mather. "By testing small tweaks to flight paths over the Atlantic, we can cut the vapour trails left behind by planes."

There is, naturally, a trade-off. Changing an aircraft's route or altitude can burn additional fuel, potentially increasing its CO₂ emissions even as it avoids a contrail. The trial will therefore need to establish whether the climate benefit of dodging persistent trails outweighs any extra fuel burned getting out of their way.

The project joins a much larger pile of taxpayer cash being pointed at greener aviation. The government announced £219 million for sustainable aviation fuel production in June and is spending another £43 million on technologies including electric and hydrogen-powered aircraft.

This experiment, though, does not require anyone to reinvent the airplane. The government and Google are betting that sometimes a greener flight path is only a few thousand feet away. ®